#define  _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <math.h>
int main() {
	double a = 0; int b = 0;
	while (scanf("%lf %d", &a, &b) != EOF) {
		double num = 0;
		double c = a;
		for (int i = 0; i < b - 1; i++)
		{
			num += pow(c, (1.0 / 2));
			c = pow(c, (1.0 / 2));
		}
		num += a;
		printf("%.2lf", num);
		printf("\n");
	}
	return 0;
}